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Determination of vehicle specifications (for example, powertrain sizing) is one of the fundamental steps in any new vehicle development process. The vehicle system engineer needs to select an optimum combination of vehicle, engine and transmission characteristics based on the product requirements received from Product Planning (PP) and Marketing teams during concept phase of any vehicle program. This process is generally iterative and requires subject matter expertise. For example, accurate powertrain sizing is essential to meet the required fuel economy (FE), performance and emission targets for different vehicle configurations. This paper analyzes existing vehicle specifications (Passenger Cars/SUVs - Gasoline/Diesel) in different automotive markets (India, Europe, US, Japan) and aims to determine underlying trends across them.

Automotive OEMs are aggressively using different materials for interiors due to value proposition and variety of options available for customers in market. Excessive usage of different grade plastics with zero gap philosophy can cause stick slip effect leading to squeak noise. Even though systems and subsystems are designed using best practices of structural design and manufacturing tolerances, extreme environmental conditions can induce contacts leading to squeak noise. Appropriate selection of interface material pairs can minimize the possibilities of squeak conditions. Stick-slip behavior of different plastics is discussed in the present study, along with critical parameters during material compatibility testing in a tribological test stand. Friction coefficient of different material pairs for a defined normal load and sliding velocity are analyzed for patterns to recognize squeaks versus time.

Currently the Automotive industry demands highly competitive product to survive in the global tough competition. The engine cooling system plays a vital role in meeting the stringent emission norms and improving the vehicle fuel economy apart from maintaining the operating temperature of engine. The airflow through vehicle subsystems like the grille, bumper, the heat exchangers, the fan and shroud and engine bay are called as front-end flow. Front end flow is crucial factor in engine cooling system as well as in determining the aerodynamic drag of vehicle. The airflow through the engine compartment is determined by the front-end vehicle geometry, the CRFM and CAC package, the engine back restriction and the engine compartment geometry including the inlet and outlet sections. This paper discusses the 1D modelling method for front-end airflow rate prediction and thermal performance by 1D method. The underbody components are stacked using heat stack and simulated in pressure mode.

Light weighting is an effective strategy in increasing energy efficiency in the automotive industry. In this paper, mass reduction with cost benefit was targeted in an exterior trim panel. Polypropylene copolymer (PPCP) compound was developed for a large exterior trim panel (1400 X 700mm) having an integrated grill mesh. The part had challenging requirements in terms of slow speed impact, structural durability, dimensional stability, aesthetics, thermal ageing resistance, cold impact resistance, scratch resistance and weathering resistance. By having ultra-high flow behavior, optimum tensile strength, modulus, impact strength and thermal properties, the PPCP compound met the requirements for a thin wall exterior trim panel with a thickness of 2.6mm. Structural durability of the design was validated by virtual engineering. Part design and material combinations with better tooling design iterations were analyzed by using mold flow analysis.

In today’s automobile industry where BS6 emission is posing a high challenge for aggregate development, cost control and with limited timeline. The main target is to provide the cooling system to have less impact on the in terms of cost, weight and to meet the challenging engineering requirement. Thus, the frugal engineering comes into the picture. This paper shows the application of thermosyphon principle for UDM injector cooling thereby reducing the rotation parts and power consumption such as an electric pump. Thermosyphon is a method of passive heat exchange and is based on natural convection, which circulates a fluid without the necessity of a mechanical or electric pump. The natural convection of the liquid commences when heat transfer to the liquid gives rise to a temperature difference from one side of the loop to the other.

Turbocharged common rail direct injection engines offer multiple benefits compared to their naturally aspirated counterparts by allowing for a significant increase in the power and torque output, while simultaneously improving the specific fuel consumption and smoke. They also make it possible for the engine to operate at a leaner air/fuel mixture ratio, thereby reducing particulate matter emission and permitting higher EGR flow rates. In the present work, a two cylinder, naturally aspirated common rail injected engine for use on a load carrier platform has been fitted with a turbocharger for improving the power and torque output, so that the engine can be used in a vehicle with a higher kerb weight. The basic architecture and hardware remain unchanged between the naturally aspirated and turbocharged versions. A fixed geometry, waste gated turbocharger with intercooling is used.

This study on optimum magnification at which Retained austenite to be evaluated by comparing the difference in determining the retained austenite in low carbon carburizing alloy steel using the optical metallurgical micrographic method and X-ray diffraction method. The retained austenite phase will be in surface and color is white in nature also its presented in between the martensite needles. It can be distinguished as separate micro-constituents by using image analyzing software. In another method the RA measurements were carried out on the surface by PROTO iXRD Retained austenite measuring system using Cr K radiation. The (211) and (200) reflections of Martensite and (220) and (200) reflections of Austenite were made for this estimation. However, the calculated values of retained austenite by metallurgical microscope in different magnifications are not identical.

Electric Vehicle is the need of an hour, as due to excessive usage of IC Engine vehicles has resulted in the depletion of the ozone layer to a significant level and fuel cost is increasing. With new technologies coming into the market, challenges come hand in hand because of Electric Vehicle. In comparison to IC Vehicle, areas of thermal management or the number of components for which thermal management needs to be done is higher and rather complex. As the thermal management system is the second highest energy consuming source after the powertrain of the electric vehicle, an efficient and reliable design is mandatory to ensure better range in an Electric Vehicle. Thermal Management of the Electric Vehicle has been identified as one of the critical parameters for balancing both cabin comfort as well as Battery temperature. One of the major concerns is meeting the Cabin comfort during colder weather with minimum energy consumption.

Serious efforts have been put in space to focus on lowering the fuel consumption and CO2 discharge to the environment from Automotive Diesel Engines. Though more focus is put on material up gradation approach on weight perspective, it is accompanied by undesirable cost increase and manufacturing complexity. As a part of development of a single cylinder engine for a light commercial vehicle application, a unique approach of integrated split type crankcase design is designed and developed. This design have addressed all the key factors on Weight, Cost and Manufacturing perspectives. The split type crankcase configuration, particularly middle-split configuration, integrates the oil sump, front cover and flywheel housing in a single unit beneficial from the point of view of reducing engine weight and thus reducing the manufacturing costs. This crankcase is also excellent from the serviceability point of view.

The automobile industry is going through one of the most challenging times, with increased competition in the market which is enforcing competitive prices of the products along with meeting the stringent emission norms. One such requirement for BS6 phase 2 emission norms is monitoring for partial failure of the component if the tailpipe emissions are higher than the OBD limits. Recently PM (soot) sensor is employed for partial failure monitoring of DPF in diesel passenger cars.. PM sensor detects soot leakage in case of DPF substrate failure. There is a cost factor along with extensive calibration efforts which are needed to ensure sensor works flawlessly. This paper deals with the development of an algorithm with which robust detection of DPF substrate failure is achieved without addition of any sensor in the aftertreatment system.

In this paper, Authors tried to investigate the influence of Low Temperature EGR (LtEGR) on NOx, PM emissions and fuel efficiency in NEDC 120 cycle. Sports Utility Vehicle (SUV) less than 3.5T vehicle selected for investigation of LtEGR. The existing water cooling circuit modified to suitable to handle the LtEGR concept without changing the existing EGR cooler. Cooled EGR technology has two benefits in terms of handling high EGR ratios and more fresh air within the engine displacement. Under this assumption separate LtEGR layout was prepared for the evolution of superior EGR cooling technologies and low pressure EGR.

The noise and vibration performance of diesel fueled automotives is critical for overall customer comfort. The stationary vehicle with engine running idle (Vehicle Idle) is a very common operating condition in city driving cycle. Hence it is most common comfort assessment criteria for diesel vehicles. Simulations and optimization of it in an early stage of product development cycle is priority for all OEMs. In vehicle idle condition, powertrain is the only major source of Noise and Vibrations. The key to First Time Right Idle NVH simulations and optimization remains being able to optimize all Transfer paths, from powertrain mounts to Driver Ear. This Paper talks about the approach established for simulations and optimization of powertrain forces entering in to frame by optimizing powertrain mount hard points and stiffness. Powertrain forces optimized through set process are further used to predict the vehicle passenger compartment noise and steering vibrations.

Model based calibration is extensively used by the automotive OEMs (Original Equipment manufacturers) because of its correlation accuracy with test data and freezing the operating parameters such as injection timings, EGR rates, fuel quantity etc. The prediction of Brake specific Fuel consumption (BSFC), Exhaust and intake temperatures are very close to test data. The prediction of Brake specific NOx is directionally reliable with acceptable tolerance.

Hydraulic Load sensing brake valves are used in vehicles from a long time in the market. They proportionate the rear brake line pressure according to the rear axle load in order to avoid the rear wheel lock during braking. During the actual test of the Hydraulic load sensing valve on a subject vehicle, there was drop in performance against its expected peak brake performance. In the current work a detailed analysis is made to understand the sensitivity of the load sensing valve & its effect on the vehicle performance. The parameters affecting the valve sensitivity along with vehicle level factors affecting the performance are analysed during the work.

Crashworthiness enhancement of vehicle structures is a very challenging task during the early design development process. Major factors influencing occupant injury in frontal impact are vehicle front crush space, crash pulse severity, restraint properties and occupant packaging space. This paper establishes a methodology to define suitable criterion that will guide the designers to select the optimal values of the above mentioned parameters during the early phase of the vehicle development. The usage of lumped mass models, pulse characterization techniques were explored to validate the results. Efficient crash energy management, the concepts of ride down and restraint efficiency parameters were also discussed in the paper.

Today’s automotive industry in the process of better fuel efficiency and aiming less carbon foot print is trying to incorporate energy saving and hybrid technologies in their products. One of the trends which has been followed by Original Equipment Manufacturers (OEMs) is the usage of Electric Power Steering (EPS) system. This has been an effective option to target fuel saving as compared to hydraulically assisted power steering system. EPS has been already tested successfully, not only on system level but also on vehicle level for endurance and performance by OEMs as per their norms and standards. Over the decade, NVH (noise, vibration & harshness) have become one of the touch points for customer perception about vehicle quality. This leads us to a commonly perceived problem in EPS or manual type steering system i.e. rattle noise.

Highly competitive automotive market demands shorter product development cycle while maintaining higher standards of performance in terms of durability and Noise Vibration & Harness (NVH). Engine cranktrain system is one of the major vibration sources in engine and first torsional mode frequency is a key parameter which influences vibration characteristics. Current CAE (Computer Aided Engineering) workflow for evaluating cranktrain system performance is time-consuming and takes around 55 Hrs. It involves crankshaft geometry cleanup, stiffness calculation, 1D model building and post processing. Over the time, significant historical data has been created while performing this virtual simulation during the product development cycle. Having a trained Machine Learning (ML) model based on this historical data, which can predict first torsional mode frequency accelerates the virtual validation. In this paper, prediction of first torsional frequency of cranktrain system using ML is presented.

Modern day automotive market demands shorter time to market. Traditional product development involves design, virtual simulation, testing and launch. Considerable amount of time being spent on virtual validation phase of product development cycle can be saved by implementing machine learning based predictive models for key performance predictions instead of traditional CAE. Durability oil canning loadcase for vehicle hood which impacts outer styling and involves time consuming CAE workflow takes around 11 days to complete analysis at all locations. Historical oil canning CAE results can be used to build ML model and predict key oil canning performances. This enables faster decision making and first-time right design. In this paper, prediction of buckling behaviour and maximum displacement of vehicle hood using ML based predictive model are presented. Key results from past CAE analysis are used for training and validating the predictive model.

Hybrid powertrains generally involve adding an electric propulsion system to an existing internal combustion engine powertrain. Due to their reduced emissions, no reliance on public infrastructure and acceptable cost of ownership, hybrids are seen as a feasible intermediate step to deliver clean and affordable transportation for the masses. Such systems are immensely complex due to the number of interplaying systems and advanced control strategies used to deliver optimum performance under widely varying loads. Resonant torsional impacts arise out of the interactions due to rotational speed variations providing impulses at specific frequencies to the spinning inertias connected by members of finite stiffness. The effects, depending on the magnitude and duration of the impacts range from unacceptably harsh vibrations to catastrophic component failure.

Noise & sound quality has gained equal importance as that of emissions and crash safety of the vehicles. With increased engine power to weight ratio, the challenges for NVH engineers has increased multifold. Passenger compartment comfort levels are getting affected largely due to lighter and powerful engines. Same time, there is pressure to reduce overall vehicle weight and cost. This impose constraints to NVH engineer in designing the body structure and sound package to reduce the effect of powertrain forces and airborne noise on passenger compartment. In addition to weight constraints, there is trend emerging to use two & three cylinder engines which need to perform on par with four cylinder engines. This has shown adverse effect on vehicle NVH performance due to wider low frequency unbalance forces.